Video Cleanup – Docker Watchdog

A Docker container that watches an input folder for new video files and automatically processes them using ffmpeg — stripping unwanted audio/subtitle tracks, removing metadata, and optionally normalizing audio. Processed files are written to an output folder; all actions are logged with timestamps.

Quick Start

# 1. Create local folders
mkdir -p input output logs

# 2. Build and start
docker compose up -d --build

# 3. Drop a video in — processing starts automatically
cp my_movie.mkv input/

# 4. Follow the log
tail -f logs/video-cleanup.log

How It Works

1. A Python watchdog monitors /input for new or moved video files
2. Waits until the file size has been stable for STABLE_SECS seconds (safe for slow network copies)
3. Calls video_cleanup.sh with the file as argument
4. The script writes the result to /output — the original in /input is never touched (unless KEEP_BACKUP=false, in which case it is removed after successful processing)
5. Every action is appended with a timestamp to /logs/video-cleanup.log

Directory Structure

.
├── Dockerfile
├── docker-compose.yml
├── README.md
├── video_cleanup.sh        # ffmpeg processing logic
└── watchdog_processor.py  # folder watcher
    
# runtime:
├── input/    ← drop videos here
├── output/   ← processed files appear here
└── logs/
    └── video-cleanup.log

Environment Variables

Variable	Default	Description
KEEP_LANGS	deu ger de	Language codes to keep (space-separated)
CLEANUP	true	Remove audio/subtitle tracks not in KEEP_LANGS
REMOVE_ALL_SUBS	false	Strip all subtitle tracks (including kept languages)
REMOVE_METADATA	false	Remove all metadata/tags from the container
NORMALIZE	false	loudnorm 2-pass audio normalization (→ AAC 192k stereo)
KEEP_BACKUP	false	Keep original as .bak in the input folder
EXTENSIONS	mkv mp4 avi ts m2ts mov	Space-separated list of monitored file extensions

Changing the Language

Edit KEEP_LANGS in docker-compose.yml:

# English only
KEEP_LANGS: "eng en"

# German + English
KEEP_LANGS: "deu ger de eng en"

# Japanese only
KEEP_LANGS: "jpn ja"

Example Configurations

Clean tracks only (keep German)

CLEANUP: "true"
KEEP_LANGS: "deu ger de"
REMOVE_ALL_SUBS: "false"
REMOVE_METADATA: "false"
NORMALIZE: "false"

Full cleanup + normalize (English)

CLEANUP: "true"
KEEP_LANGS: "eng en"
REMOVE_ALL_SUBS: "true"
REMOVE_METADATA: "true"
NORMALIZE: "true"

Log Format

2025-03-15 14:23:01 [INFO] New file detected: /input/movie.mkv
2025-03-15 14:23:06 [INFO] Processing: /input/movie.mkv
2025-03-15 14:23:06 [INFO]   Keep languages : deu ger de
2025-03-15 14:23:06 [INFO]   Audio tracks: 3 | Subtitles: 2
2025-03-15 14:23:06 [INFO]   Audio  #1: lang=deu  ✔ keep
2025-03-15 14:23:06 [INFO]   Audio  #2: lang=eng  ✘ remove
2025-03-15 14:23:06 [INFO]   Audio  #3: lang=und  ✘ remove
2025-03-15 14:23:06 [INFO]   → Starting cleanup...
2025-03-15 14:23:44 [INFO]   ✔ Cleaned → /output/movie.mkv
2025-03-15 14:23:45 [INFO] ✔ Successfully processed: /input/movie.mkv

Requirements

• Docker Engine 24+ with Compose v2
• The container ships with ffmpeg from the Debian package repos.